(19)
(11) EP 0 697 188 B2

(12) NEW EUROPEAN PATENT SPECIFICATION

(45) Date of publication and mentionof the opposition decision:
09.02.2005 Bulletin 2005/06

(45) Mention of the grant of the patent:
31.10.2001 Bulletin 2001/44

(21) Application number: 95201934.7

(22) Date of filing: 13.07.1995
(51) International Patent Classification (IPC)7A47L 15/42

(54)

Device for controlling the flow of washing liquid for feeding the spraying rotors of a dishwasher machine

Waschwasserzufuhrkontrolle für Sprüharme einer Geschirrspülmaschine

Dispositif pour le dosage contrôlé de liquide de lavage pour les bras d'arrosage d'une machine à laver la vaisselle


(84) Designated Contracting States:
DE FR IT

(30) Priority: 27.07.1994 IT MI941602

(43) Date of publication of application:
21.02.1996 Bulletin 1996/08

(73) Proprietor: CANDY S.p.A.
I-20052 Monza (Milano) (IT)

(72) Inventor:
  • Fumagalli, Silvano
    I-20052 Monza (IT)

(74) Representative: Mittler, Enrico et al
Mittler & C. s.r.l., Viale Lombardia, 20
20131 Milano
20131 Milano (IT)


(56) References cited: : 
DE-A- 2 345 908
DE-A- 3 406 698
DE-A- 3 911 305
DE-A- 8 806 160
FR-A- 2 457 670
US-A- 4 730 630
DE-A- 3 014 663
DE-A- 3 441 023
DE-A- 7 044 916
FR-A- 2 443 231
FR-A- 2 651 427
   
       


    Description


    [0001] The present invention relates to a device for controlling the flow of washing liquid for feeding the spraying rotors of a dishwasher machine.

    [0002] Known dishwasher machines comprise a washing tub in which two horizontal shelves are slidingly housed to hold the dishes to be washed, situated at the bottom (lower shelf) and mid-height (upper shelf) respectively of the washing tub. Two spraying rotors, lower and upper respectively, are associated to said shelves and fed with the washing liquid (mixture of water and detergent) by a motor pump connected to a sump located below the bottom of the washing tub and wherein the washing liquid diffused by the spraying rotors is collected.

    [0003] In most dishwashers the two rotors are fed simultaneously, assuming that both the shelves have been loaded with dishes to be washed. The quantity of water which has to be fed into the tub of the dishwasher has to be such that the pump does not go into cavitation and that the pressure of the water emitted by the rotors is not too low.

    [0004] Nevertheless the growing interest in dishwashers which require smaller volumes of water, with a consequent saving in detergent and electrical energy for heating the washing liquid, is known. For this purpose devices for controlling the flow of liquid sent by the pump to the rotors have been introduced and which allow one rotor to be fed at a time alternately. In this way the volume of water required by the dishwasher is smaller because the two rotors never operate simultaneously and the quantity of liquid in circulation is smaller. These are substantially devices for diverting the flow of washing liquid and are placed between the pump and the pipes for feeding liquid to the rotors, inside of which a cut-off part moves alternatively between two working positions, in each of which one of the pipes is closed while the other is open. The movement of the cut-off part is achieved either by means of an actuator or under the thrust of the liquid itself, the two working positions in this case being positions of instable equilibrium.

    [0005] Nevertheless these devices too, due to the fact that the washing liquid is any case fed to both rotors, assume that both shelves are loaded with dishes to be washed. This can be inconvenient in some dishwashers which have differentiated programmes for washing twelve or six table settings. In this second case in fact it would be more useful to load all the dishes on the upper shelf alone (both for reasons of convenience for the user and better washing results, given that the temperature in the washing tub is higher at the top than at the bottom), and to feed only the upper rotor

    [0006] DE-A-7 044 916 discloses a device according to the preamble of claim 1.

    [0007] In view of the state of the art described here, the object of the present invention is that of providing a device for controlling the flow of washing liquid for feeding the spraying rotors which overcomes the aforementioned disadvantages.

    [0008] In accordance with the present invention, this object is achieved thanks to a device for controlling the flow of washing liquid for feeding a first spraying rotor and a second spraying rotor of a dishwasher as set forth in claim 1.

    [0009] The control device according to the present invention enables continuous or discontinuous feeding of one of the two spraying rotors, while the other one can be independently fed or not. The rotor associated to the outlet conduit controlled by said cut-off means is preferably the lower one so that, should the dishwasher be programmed for washing six table settings, the dishes can be loaded on only the upper shelf, and the flow rate and pressure of the pump fully exploited to feed the washing liquid to the upper rotor alone.

    [0010] These and other features of the present invention will be made clearer by the following detailed desctiption of some of its embodiments, illustrated by way of a non-limiting example in the accompanying drawings, in which:

    Figure 1 is a section along a vertical plane of a dishwasher equipped with a control device according to a first embodiment of the present invention;

    Figure 2 is a section along line II-II of Figure 1;

    Figure 3 is a section along line III-III of Figure 1;

    Figure 4 is a section along a vertical plane of a dishwasher equipped with said control device, during washing of a complete load of dishes;

    Figure 5 is similar to Figure 1, but referred to the case of washing a partial load of dishes.



    [0011] Figure 1 shows a washing tub 1 of a dishwasher, below which washing tub 1 a sump 2, wherein the washing liquid is collected, is mounted. Connected to the sump 2 is a motor pump 3 which, taking the liquid from the sump 2, sends it to a lower spraying rotor 4 extending from the bottom of the tub 1 inside the latter and related to a lower loading shelf 100 and to an upper spraying rotor 4', positioned approximately at mid-height inside the tub 1 and related to an upper loading shelf 101 (Figs. 4 and 5).

    [0012] Connected to the outlet conduit 5 of the coil 6 of the pump 3 is a device 7 for cutting off the flow of washing liquid, consisting of a chamber 8 wherein a diaphragm 9, moving between two working conditions (shown as an unbroken line and dotted and dashed line respectively in Figure 1), is hinged. Above the chamber 8 a substantially cylindrical outlet conduit 10 is connected, divided internally into two semicylindrical conduits 11 and 12 by a baffle 13 (Fig. 2). Connected to the outlet conduit 10 is a flow diverter 14, also substantially cylindrical, and wherein a baffle 15, having a substantially vertical lower section 18, is also provided and which divides internally the flow diverter 14 into two semicylindrical conduits 16 and 17, and an upper elbow section 19 which joins the semicylindrical conduit 17 to a horizontal cylindrical conduit 20 for feeding the upperspray-ing rotor 4'. The flow diverter 14 is inserted in a special hole 21 of the tub 1, and is attached by means of a ring nut 22. The lower spraying rotor 4 is mounted, freely rotatably, above the flow diverter 14

    [0013] The diaphragm 9 has dimensions which correspond substantially to those of the chamber 8, and is attached at one end to a pin 24. Outside of the chamber 8 the pin 24 is connected to an actuator 25 which causes displacement of the diaphragm 9 into the two working positions. The diaphragm 9 has a semicircular opening 23 which, when the diaphragm 9 is in the closure position shown by a dashed and dotted line in Figure 1, is positioned below the mouth of the semicylindrical conduit 12.

    [0014] When the diaphragm 9 is in the opening position (shown by an unbroken line in Figure 1), both the semicylindrical conduits 11 and 12 are open, and the water coming from the outlet conduit 5 of the pump 3 is distributed among the semicylindrical conduits 11, 16 and 12, 17, thus feeding simultaneously both the lower rotor 4 and the upper rotor 4' (Fig. 4). When the diaphragm 9 is in the closure position, the mouth of the semicylindrical conduit 11 is closed, while the mouth of the semicylindrical conduit 12 is open; thus feeding of the lower rotor 4 is interrupted, while the upper rotor 4' continues to be fed (Fig. 5),


    Claims

    1. Device for controlling the flow of washing liquid for feeding a first spraying rotor (4) and a second spraying rotor (4') of a dishwasher, comprising an inlet conduit (5) connected to means for pumping the washing liquid, at least a first outlet conduit (11) and a second outlet conduit (12;20) connected respectively to said first and second spraying rotors (4,4'), and means (9) for controlling the flow of liquid from said inlet conduit (5) to said outlet conduits (11), wherein said means (9) comprises first means (9) associated to said first outlet conduit (11) for controlling the opening and closure thereof and therefore selectively cutting off the flow of liquid from the inlet conduit (5) to the first outlet conduit (11), the second outlet conduit (12) is being left constantly open so that the second spraying rotor (4') is always fed, during the washing cycle, characterised in that said first outlet conduit and second outlet conduit are respectively a first semicylindrical portion (11) and a second semicylindrical portion (12) of a cylindrical conduit (10) defined by a baffle (13) inside said cylindrical conduit (10), said first cut-off means comprising a diaphragm (9) which can be rotated between an opening position and a closure position of said first semicylindrical portion (11) of the cylindrical conduit (10).
     
    2. Control device according to claim 1, characterised in that said first spraying rotor (4) is associated to a lower loading shelf (100), and said second spraying rotor (4') is related to an upper Loading shelf (101).
     


    Ansprüche

    1. Vorrichtung zum Steuern des Flusses einer Waschflüssigkeit zum Versorgen eines ersten Sprührotors (4) und eines zweiten Sprührotors (4') einer Geschirrspülmaschine, mit einer Einlaßdurchführung (5), die mit einer Einrichtung zum Pumpen der Waschflüssigkeit verbunden ist, wenigstens einer ersten Auslaßdurchführung (11) und einer zweiten Auslaßdurchführung (12; 20), die jeweils mit dem ersten und dem zweiten Sprührotor (4, 4') verbunden sind, und einer Einrichtung (9) zum Steuern dec Flusses von Flüssigkeit von der Einlaßdurchführung (5) zu den Auclaßdurchführungen (11), wobei die Einrichtung (9) eine der ersten Auslaßdurchführung (11) zugeordnete erste Einrichtung (9) zum Steuern ihrec Öffnens und Schließens und daher zum selektiven Sperren des Flusses von Flüssigkeit von der Einlaßdurchführung (5) zur ersten Auslaßdurchführung (11) aufweist, die zweite Auslaßdurchführung (12) konstant offen gelassen wird, so daß der zweite Sprührotor (4') während des Waschzyklus immer versorgt wird, dadurch gekennzeichnet, daß die erste Auslaßdurchführung und die zweite Auclaßdurchführung jeweils ein erster semizylindrischer Teil (11) und ein zweiter semizylindrischer Teil (12) einer zylindrischen Durchführung (10) sind, die durch eine Einbauplatte (13) innerhalb der zylindrischen Durchführung (10) definiert sind, wobei die erste Sperreinrichtung eine Membran (9) aufweist, die zwischen einer Öffnungsposition und einer Schließposition des ersten semizylindrischen Teils (11) der zylindrischen Durchführung (10) gedreht werden kann.
     
    2. Steuervorrichtung nach Anspruch 1, dadurch gekennzeichnet, daß der erste Sprührotor (4) zu einem unteren Beladeabteil (100) gehört und der zweite Sprührotor (4') zu einem oberen Beladeabteil (101) gehört.
     


    Revendications

    1. Dispositif pour la commande de l'écoulement de liquide de lavage pour l'alimentation d'un premier rotor de pulvérisation (4) et d'un deuxième rotor de pulvérisation (4') d'un lave-vaisselle, comportant une conduite d'entrée (5) reliée à des moyens de pompage du liquide de lavage, au moins une première conduite de sortie (11) et une deuxième conduite de sortie (12; 20) reliées respectivement aux dits premier et deuxième rotors de pulvérisation (4, 4'), et des moyens (9) destinés à commander l'écoulement de liquide depuis ladite conduite d'entrée (5) vers lesdites conduites de sortie (11), dans lequel lesdits moyens (9) comportent des premiers moyens (9) associés à ladite première conduite de sortie (11) afin de commander l'ouverture et la fermeture de celle-ci et par conséquent couper de manière sélective l'écoulement de liquide de la conduite d'entrée (5) vers la première conduite de sortie (11), la deuxième conduite de sortie (12) est laissée constamment ouverte de sorte que le deuxième rotor de pulvérisation (4') est toujours alimenté, pendant le cycle de lavage, caractérisé en ce que ladite première conduite de sortie et ladite deuxième conduite de sortie sont respectivement une première partie semi-cylindrique (11) et une deuxième partie semi-cylindrique (12) d'une conduite cylindrique (10) définie par une chicane (13) à l'intérieur de ladite conduite cylindrique (10), lesdits premiers moyens de coupure comportant un diaphragme (9) qui peut être entraîné en rotation entre une position d'ouverture et une position de fermeture de ladite première partie semi-cylindrique (11) de la conduite cylindrique (10).
     
    2. Dispositif de commande selon la revendication 1, caractérisé en ce que ledit premier rotor de pulvérisation (4) est associé à un plateau de chargement inférieur (100), et ledit deuxième rotor de pulvérisation (4') est lié à un plateau de chargement supérieur (101).
     




    Drawing